Did anyone plumb this valve to the fuel tank/charcoal canister?
:huh:
:huh:
EVAP Solenoid Valve LS3
- Thread starter Dan carter
- Start date
Ken Roberts
Supporter
I have the complete EVAP system in use in my build. It includes the vent solenoid, purge solenoid, fuel tank pressure sender and charcoal canister. Both solenoids are timed/controlled to open and close from the ECM. For the system to work correctly all four items must be used.
Ken Roberts
Supporter
The first picture shows the purge solenoid and nylon tubing that eventually leads to the charcoal canister.
The second picture shows me pointing to where the purge solenoid connects at the canister.
The second picture shows me pointing to where the purge solenoid connects at the canister.
Ken Roberts
Supporter
This picture shows me pointing to where the fuel tank vent is connected at the canister.
This picture shows me pointing to the vent solenoid. This solenoid opens and closes the fresh air supply for the canister. If the system commands a leak test then this solenoid will close and the ECM will open the purge solenoid at the engine. The ECM will then watch to see that a vacuum has been created in the fuel tank via the fuel tank pressure sensor. This is all part of the OBD2 diagnostics that all production cars must have.
This picture shows me pointing to the vent solenoid. This solenoid opens and closes the fresh air supply for the canister. If the system commands a leak test then this solenoid will close and the ECM will open the purge solenoid at the engine. The ECM will then watch to see that a vacuum has been created in the fuel tank via the fuel tank pressure sensor. This is all part of the OBD2 diagnostics that all production cars must have.
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Ken Roberts
Supporter
This picture shows me pointing to the fuel tank pressure sensor that is mounted on the top of the module at the tank. You can also see the third nylon fuel tubing (the one in the middle) that vents fuel vapors to the canister. It has a built in roll over valve to prevent fuel from dumping into the canister if the car is inverted.
Ken Roberts
Supporter
In addition I modified a production C6 Corvette fuel filler and cap so that I would be sure the fuel tank is sealed correctly when the vacuum test is commanded.
Ken. Do you have a list of parts you used. They look like GM parts??? The last entry may have lost the picture. I would really benefit from your pictures on this set up......what connected where and placement. Have a build log perhaps?
Ken Roberts
Supporter
I have a build log but really didn't go into much about the EVAP system. It does show how I built the Corvette fuel filler though. I can provide some part numbers for you if you decide to tackle it. Every part is from GM. Be aware of the following though:
1- For the system to work as designed the fuel level has to be read by the ECM and your fuel level gauge (not to just your fuel level gauge). You will need to add the wires to the ECM connectors.
2- You need to weld a bung to your fuel tank so that a vacuum/fuel hose can be hooked up to the fuel tank pressure sensor.
3- The fuel tank pressure sensor has three wires that need to be added to the ECM connectors.
4- The vent solenoid has two wires that need to be added to the ECM connectors.
5- Vehicle speed sensor must be hooked up to ECM as well as speedo.
6- Hp Tuners or EFI live will be needed to enrol the system
1- For the system to work as designed the fuel level has to be read by the ECM and your fuel level gauge (not to just your fuel level gauge). You will need to add the wires to the ECM connectors.
2- You need to weld a bung to your fuel tank so that a vacuum/fuel hose can be hooked up to the fuel tank pressure sensor.
3- The fuel tank pressure sensor has three wires that need to be added to the ECM connectors.
4- The vent solenoid has two wires that need to be added to the ECM connectors.
5- Vehicle speed sensor must be hooked up to ECM as well as speedo.
6- Hp Tuners or EFI live will be needed to enrol the system
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Ken Roberts
Supporter
Basic operation
The purge solenoid will open at the intake manifold for a brief period to allow fuel vapors that have been collected in the charcoal canister to be pulled into the intake air stream. The ECM watches the fuel level in the tank and the vehicle speed to determine when to command this operation. The vent solenoid at the canister "at this time" is commanded to the open position to allow fresh air into the canister to replace the soiled air being sucked into the manifold.
After so many hours of operation a self test is commanded to check for system integrity. At this time the purge solenoid at the intake opens to pull vapors into the engine but what's different is the vent solenoid at the canister is commanded to be closed. The system is now sealed from the atmosphere. A vacuum is now created that is measured in the fuel tank by the pressure sensor. The ECM watches the fuel level to determine how much air space is in the tank and then watches the pressure sensor to see if a vacuum is maintained. That's the number one reason why you will get a diagnostic lamp indication if the fuel tank cap is loose, missing or has a poor seal. It has failed the vacuum test.
Unless your State is very picky about emissions it's a lot of work to get it working as designed.
The purge solenoid will open at the intake manifold for a brief period to allow fuel vapors that have been collected in the charcoal canister to be pulled into the intake air stream. The ECM watches the fuel level in the tank and the vehicle speed to determine when to command this operation. The vent solenoid at the canister "at this time" is commanded to the open position to allow fresh air into the canister to replace the soiled air being sucked into the manifold.
After so many hours of operation a self test is commanded to check for system integrity. At this time the purge solenoid at the intake opens to pull vapors into the engine but what's different is the vent solenoid at the canister is commanded to be closed. The system is now sealed from the atmosphere. A vacuum is now created that is measured in the fuel tank by the pressure sensor. The ECM watches the fuel level to determine how much air space is in the tank and then watches the pressure sensor to see if a vacuum is maintained. That's the number one reason why you will get a diagnostic lamp indication if the fuel tank cap is loose, missing or has a poor seal. It has failed the vacuum test.
Unless your State is very picky about emissions it's a lot of work to get it working as designed.
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Ken Roberts
Supporter
Here is a look at the position I chose to mount the charcoal canister. It can be serviced from this position without having to remove the body.
Ken Roberts
Supporter
You could also dumb it down a bit like the E Rod system. It uses the charcoal canister and the purge solenoid only. The vent solenoid and fuel tank pressure sensor is omitted. The only difference is it will not do a self test to check for leaks (no self diagnostics).
The charcoal canister remains open at all times to atmosphere. A vehicle speed input to the ECM is still required. I'm not sure about this....but I think a fuel level input to the ECM is advisable for optimal operation.
For safety a roll over valve is required for the vent line to the charcoal canister. This is very important. If not installed and your vehicle flips over.....fuel will dump out the charcoal canister.
The E Rod instructions also mentions that a 2006 or newer production fuel filler and cap are required for proper operation.
The charcoal canister remains open at all times to atmosphere. A vehicle speed input to the ECM is still required. I'm not sure about this....but I think a fuel level input to the ECM is advisable for optimal operation.
For safety a roll over valve is required for the vent line to the charcoal canister. This is very important. If not installed and your vehicle flips over.....fuel will dump out the charcoal canister.
The E Rod instructions also mentions that a 2006 or newer production fuel filler and cap are required for proper operation.
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Ken
That is some project to make it all work. I wrote GM performance a question about my ECM and harness as it lacks a power harness to even power the solenoid up. That make me wonder if the ECM even has the EVAP programmed.
They even omitted the oil level sensor hookup..........hummm.
I am going to have to read your solution slowly, very slowly.....lol
BTW, what type of hose did you use to hook up the PVC breather lines. I don't want to use rubber fuel hose, its too thick and bulky.
Thanks
That is some project to make it all work. I wrote GM performance a question about my ECM and harness as it lacks a power harness to even power the solenoid up. That make me wonder if the ECM even has the EVAP programmed.
They even omitted the oil level sensor hookup..........hummm.
I am going to have to read your solution slowly, very slowly.....lol
BTW, what type of hose did you use to hook up the PVC breather lines. I don't want to use rubber fuel hose, its too thick and bulky.
Thanks
Ken Roberts
Supporter
I used nylon fuel tubing (the same as OEM) for my evap lines. You can buy it in a 20 foot roll for about $10 to $20. The fittings are available too. All can be purchased at Summit Racing. The manufacture is Dorman. These are also easily found at your local auto parts stores as well.
I believe the EVAP operation is already in the factory GMPP tune. They just change the fault codes to be not reportable. You would need to change the codes to be reportable with tuning software such as HP Tuners.
You can add the two wires to the ECM connector. I can give you a lead as to who sells the needed pins. There is even online tutorials as how to add pins (circuits) to your ECM plugs.
I believe the EVAP operation is already in the factory GMPP tune. They just change the fault codes to be not reportable. You would need to change the codes to be reportable with tuning software such as HP Tuners.
You can add the two wires to the ECM connector. I can give you a lead as to who sells the needed pins. There is even online tutorials as how to add pins (circuits) to your ECM plugs.
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Sure, since you have already done it, the leads and pins will be added to the to do library.
I got a lot of work ahead of me.....once the car gets here.
Thanks
I got a lot of work ahead of me.....once the car gets here.
Thanks
GM confirmed for me today that the the EVAP solenoid valve is not wired in their wire harness for the LS3 376/480 crate motor. They said it can be removed.
Ken Roberts
Supporter
If removed be sure to cap the tube into the intake manifold
Thanks Ken. Still undecided but I still have a few weeks for full delivery.
